Drilling-machine.



No. 767,282. PATENTED AUG. 9, 1904 H. B. KEIPER.

DRILLING MACHINE.

APPLICATION FILED DEC. 27. 1902.

N0 MODEL. 2 SHEETS-SHEET 1 Y mu M L nden I'oz M 1V1 human i Q A No.767,282. PATENTED AUG. 9, 1904. H. B. KEIPER. DRILLING MACHINE.

APPLICATION FILED DEC. 27. 1902. K0 MODEL.

2 SHEETS-SHEET 2.

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UNITED STATES Patented August 9, 1904.

PATENT OFFICE.

DRILLING-MACHINE.

SPECIFICATION forming part of Letters Patent No. 767,282, dated August9, 1904.

Application filed December 27, 1902. Serial No. 136,855. (No model.)

To (all whom, it may concern.-

Be it known that I, HENRY B. KEIPER, acitizen of the United States,residing at Lancaster, in the county of Lancaster and State ofPennsylvania, have invented certain new and useful Improvements inDrilling-Machines; and I do hereby declare the following to be a full,clear, and exact description of the invention, such as will enableothers skilled in the art to which it appertains to make and use thesame.

This invention relates to drilling-machines of that type in which thedrill-spindle is coupled to a non-rotatable feed-screw fitted in arotatable feed-nut or quill which is turned to move the screwlongitudinally, and thus feed the drill. After the hole in theworkpiece'is drilled it becomes necessary, of course, to return thefeed-screw to its primary position, so as to withdraw the bit and beready for the next drilling operation. This is usually accomplished byreversing or unscrewing the feed-nut, so as to move the screw in adirection opposite to its feed movement, which, as well known, isgenerally a long tiresome Various devices have been employed foreffecting a quick return of the screw and connected parts-for instance,a crank-wheel and suitable gearing for rotating the feed-nut or quillreversely; but nevertheless such return action necessitates theconsumption of more or less time and effort, ex-

cept where it is automatically performed in a power-machine.

The principal object of the present invention is to provide improvedfeeding mechanism in machines of the character stated whereby thefeed-screw and drill-spindle coupled thereto can be lowered or advancedfreely to bring the drill to the work, then gradually moved by rotationof the feed-nut to feed the drill in the usual way, and instantlyreturned to withdraw the drill without the necessity of unscrewing orreversely rotating the feednut.

The invention will first be described with reference to the accompanyingdrawings, which form a part of this specification, and will then bepointed out more particularly in the annexed claims.

In said drawings I have illustrated my invention embodied in a verticalor upright drill of well-known construction; but it will be understoodthat the invention is susceptible of general application and canadvantageously be applied to horizontal, angular, and other types ofdrills, as well as boring or other analogous machines.

Figure 1 is a side elevation of said machine having my inventionembodied therein, the base and work-supporting table being not shown.Fig. 2 is a similar enlarged elevation of the feeding mechanism, therotatable feed-nut and its connected partsbeing in section. Fig. 3 is ahorizontal section on line 3 3 of Fig. 2 looking upward as indicated bythe arrows. Fig. iis a horizontal section on line i 4 of Fig. 2, showingthe movable screwthreaded devices in the feed-nut engaging thefeed-screw. Fig. 5 is asection similar to Fig. 4, showing the saiddevices not engaging the feed-screw. Fig. 6 is a bottom plan view of thefeed-nut and its bottom collar for operating said engaging or grippingdevices. Fig. 7 is a side elevation of the feeding mechanism with adifferent device from that shown in Figs. 1, 2, and 3 for turning orrotating the feed-nut.

In the drawings, A designates the frame of the machine.

The letterB denotes the drill-spindle, which may be driven by gears Cand D, operated either by hand or power. This drill-spindle, which issplined to its gear so as to move up and down in the usual way, isconnected by any loose coupling E to the feed-screw F.

Preferably a lever G is employed for raising and lowering the drill whenthe feed-screw is disengaged from its feed-nut and allowed free verticalmovement therein. Said lever, which may be fulcrumed to a swinging linkH, depending from the upper part of the machine-frame, is shownconnected to the coupling E, and its rear arm carries a weight J, housedin the hollow backbone of the frame. This weight should be heavy enoughto lift the spindle and withdraw the drill when the feed-screw isdisengaged from its feed-nut and allowed free play in the mannerhereinafter explained.

The letter K, Figs. 1 to 65, inclusive, denotes the feed-nut, byrotation of which the screw is moved downward to feed the drill. Saidfeed-nut, comprising a sleeve or tubular body with means for engagingand coacting with the screw, journaled in a bearing L at the upper partof the machine-frame, and, as shown, it is held in position by a collarM, rigidly attached to its upper end, as by asetscrew or set-screws,Figs. 1, 3, and 7, as well as by a ring or collar N, secured tightly toits lower end, so as to rotate with the nut, but also capable of beingturned a certain distance independently for a purpose presentlyexplained. The ring N is shown in Fig. 2 formed with an inner flangewhich fits between the bottom of the bearing L and an outer flange onthe lower end of the feed-nut, thus holding said ring in place.

The feed-nut does not constantly engage the feed-screw, as in theordinary construction of machines of the present character, but has acentral bore loosely receiving said screw and. has one or more,preferably two, screw threaded gripping devices adapted to be closed ormoved inward'to engage the screw and to be opened or moved outward torelease the same.

In the construction illustrated an oppositely-disposed pair of suchgripping devices are shown, (designated by the letter 0, Figs. 2, 4, andThey consist of blocks fitted in transverse or radial slideways in thefeed-nut and having their confronting faces screwthreaded to engage andcoact with the feedscrew. Said blocks are shown formed transversely withthe vertical slots or slightlyel'ongated apertures in which are locatedsuitable rings or cylinders I, which are set eccentrically on verticalrods or bolts R, fitted in bearings in the sleeve or body of the feednutabove and below the slideways and gripping devices or blocks. Anyequivalent eccentric devices may of course be employed. Removablebushings Q may be provided for said rods to prevent wear of the sleeve.The lower ends of these rods are shown provided with toothed pinions S,which engage short annular or segmental. racks T on the bottom of thering N, said racks having, preferably, suitable projections at theirends to limit their movement with respect to the pinions. A singleannular rack or gear could be employed in some instances, and othermeans may be employed for moving the block in and out.

When the ring N is in one position, as represented in Fig. 6, the rodsRhold the eccentrics I in such position as to keep the gripping devicesor screw-threaded blocks 0 in engagement with the feed-screw, as shownin Fig. 4, so that as the feed-nut is rotated the screw is graduallymoved to feed the drill; but when the ring N is turned to its otherposition the pinions are turned by the racks, (about a halfturn in thepresent instance',) so that the eccentrics swing around and move thegripping devices outward, as indicated in Fig. 5, so that the screw canmove freely through the feednut. It will be observed that in Fig. i thelonger radii of the eccentrics are interposed between their axes and theinnermost sides of the apertures in the blocks 0, while in Fig. 5saidlonger radii are interposed between said axes and the outermost sides ofsaid apertures. The bearing L is shown formed interiorly with an annularrecess to receive the outer faces of the blocks 0 when they are openedor moved away from the feed-screw. By this means the feed-nut can bedisengaged from the feed-screw, so that the drill-spindle can beadjusted by the lever G to its proper position to start the drillingoperation. Then the feed-nut can be caused to engage the screw, and whensaid nut is rotated the screw will move and feed the drill. hen thedrilling operation is completed or when it is desired to withdraw thedrill at any time, the feed-nut can be disengaged by turning the ring N,which may have a milled surface, as shown, for convenient manipulation,and thereupon the drillspindle will be raised or returned instantly toits normal or initial starting position by the weight J. The drill canthen be lowered to any desired position and the work continued by againengaging the nut and screw.

In place of the weight J on lever G any suitably-arranged weight orother device may be connected to the feed-screw for effecting an instantreturn movement, or such weight or device may be dispensed with and thespindle may be raised and lowered entirely by the lever or by othermeans or by the hand of the operator directly. However, the constructionshown is preferred.

Any suitable means may be employed for rotating the feed-nut. In Fig. 3a worm or endless screw U is shown engaging an annular series of teeth Von the body of the nut. The worm-shaft has rigidly mounted on its frontend a crank-wheel N for rotating it by hand, and it has alsoaratchet-wheel X there on engaged by a pawl carried by a lever Y, whichis suitably connected to the driving mechanism to turn the worm-shaftautomatically. In Fig. 7 the worm is dispensed with and a ratchet-wheelZ is formed on or secured to the collar M, engaged by a ratchet on anautomatically-operated lever. Both constructions are well known, andhence further description is deemed. unnecessary.

The invention is susceptible of various changes in details ofconstruction and arrangement without departing from, its scope.

Having thus fully described my invention, what I claim as new, anddesire to secure by Letters Patent of the United States, is

1. In a drilling-machine, the combination with the drill-spindle coupledto a feed-screw, of a rotatable feed-nut inclosing said screw andadapted to engage or disengage the same,

and means for operating said feed-nut to engage or disengage said screw,whereby the screw can be advanced to feed the drill or allowed to movefreely in the feed-nut when disengaged by the latter, means for quicklyreturning the feed-screw to normal position when disengaged, and meansfor rotating said feed-nut, substantially as described.

2. In a drilling-machine, the combination with the drill-spindle coupledto a feed-screw, of a feed-nut for said screw comprising a rotatablebody, having an axial opening through which the screw can move freely, amovable device carried thereby having screw-threads to coact with thescrew, a rod journaled in said body having a pinion thereon andeccentrically connected to said movable device, and a rack engaging saidpinion and rotatable with said body but capable of being turnedindependently, whereby said device can be caused to engage and disengagethe screw, and means for rotating said feed-nut, substantially asdescribed.

3. In a drilling-machine, the combination with the drill-spindle coupledto a feed-screw, of a feed-nut for said screw comprising a rotatablebody, having an axial opening through which the screw can move freely,and a number of transversely-movable devices carried by said body havingscrew-threads on their inner faces adapted to coact with the screw, rodsjournaled in said body eccentrically connected to said devices, andhaving pinions thereon, and a ring rotatable with said body but capableof an independent turning having an annular rack or racks engaging saidpinions, wherebysaid ring may be turned to cause said devices to move inand out to engage and disengage the screw, and means for rotating saidfeed-nut, substantially as described.

4. In a drilling-machine, the combination with the drill-spindle coupledto a feed-screw, of a rotatable body loosely inclosing said screw havingtransverse or radial slideways therein, movable blocks fitted in saidslideways having screw-threads on their inner faces adapted to coactwith the screw, for advancing theIatter by the rotation of said body,

with the drill-spindle coupled to a feed-screw, of a feednut for saidscrew comprisinga body having an axial opening through which the screwcan move freely, transversely-movable devices carried by said bodyscrew-threaded on their inner faces to coact with the screw, rodsjournaled in said body having eccentric parts located in transverseslots in said desaid feed-nut and having a rack or racks engaging saidpinions, substantially as described.

7. In a drilling-machine, a non-rotatable feed-screw and a drill-spindlecoupled thereto for longitudinal movement therewith while permittingindependent rotation thereof, in combination with a rotatable feed-nuthaving means for engaging the screw to advance the latter when saidfeed-nut is rotated, means for rotating said feed-nut, means forreleasing the screw from said engaging means, and means for quicklyautomatically returning the feedscrew to its normal position whenreleased by said engaging a means, substantially as described.

8. In combination with a non-rotating feedscrew, a rotatable bodythrough which said screw passes,'means carried by said body for engagingthe threads of said screw to advance the latter by the rotation of saidbody, means for rotating said body, means for releasing the screw fromsaid engaging means, and means for adjusting the screw and feeding byhand independently of the action of said rotating body when the screw isreleased by said engaging means, substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

HENRY B. KEIPER."

Witnesses:

J. GUY ESHLEMAN, L. B. KEIPER.

